1. Field of the Invention
The present invention relates generally to insulated biologic specimen shipping containers and their associated components, and relates more specifically to those containers used to keep items within them warm, especially when being shipped during winter months to or from areas with colder climates. Where relevant, these containers and associated components, referred to as a system or kit, must comply with regulatory shipping requirements for biologic/diagnostic samples, and are employed when non-frozen tissues, such as blood etc., are shipped overnight in an attempt to conduct testing and analysis on viable living tissues or specimens.
2. Description of Related Art
Conventional insulated shipping containers that are typically used for shipping biologic/diagnostic samples employ foamed polymeric materials, such as polystyrene, which are used to provide one layer of insulation, and then this container is placed within a plastic bag and the combination is the placed within a cardboard box (or additional insulated container(s)) to maintain as much passive insulation as possible between the specimens and the surrounding environment. Such insulation materials are typically comprised of polyurethane or foamed polystyrene.
In addition to maintaining the specimen at the desired temperature, the shipment of diagnostic specimens must also conform to public safety standards, i.e. specific shipping regulations to protect the general public and all those who handle the container containing the biologic specimen during shipping. Any human diagnostic or biologic samples with the potential to be infectious or hazardous have to be shipped in compliance with specific packaging requirements for such materials. These standards are issued by the U.S. Postal Service (Domestic Mail Manual, DMM 601.10.17) in the United States, and by other similar authority on other countries. Thus, regardless of the requirements for viability, blood specimens and other biologic fluids or tissues for research or diagnostic laboratory testing are generally categorized as biologic diagnostic specimens, and the shipment of which must satisfy the postal packaging regulations in accordance with 49 C.F.R. §30 173.196, in the United States, or with the requirements of the relevant regulatory authority in other countries.
Previous packaging for such materials was typically in the form of pre-formed passive insulating package components, consisting by code of absorbent material, an insulating foam package, and an airtight plastic bag or pouch, all of which are placed inside a cardboard shipping container. These components lack an adequate way of maintaining sample temperature in cold weather shipping conditions for the duration of the shipping time. The passive insulation within these shipping containers typically included rigid foam components in attempts to provide the desired protection against temperature variation during shipment.
However, even when taken to the impractical extreme of placing several insulated containers within one another, such configurations involving passive foam insulation are insufficient, when environmental temperatures are below certain thresholds, to keep biologic samples from freezing, even over the course of expedited overnight shipping. Living cells within the tissues or fluids would freeze, or come close to freezing and lose viability, or specimen fidelity could be endangered to the point of becoming diagnostically or analytically compromised.
The maintenance of room temperature, or at least temperatures above freezing, over the course of shipping is critical for many human diagnostic tests where live immune cells are collected from blood tubes and their response to different conditions (e.g. antigens) is assayed or measured. Thus, there is a great need for an improved shipping container and method for keeping samples at near room temperature (or under non-freezing conditions) when shipping biologic specimens during the winter months. Biological samples that are shipped overnight during the winter months may freeze or reach temperatures near 0° C., at which point the cells lose viability (i.e., die). The present invention provides such a practical container system and method of winter temperature maintenance for shipping biologic specimens. The method and device will keep biologic specimens at biologically viable temperatures (40-98 degrees F. or 4.4° to 36.7° C.) when shipping overnight. The device will safely facilitate extended storage and transport of the samples at below ambient temperatures during winter months in situations when shipping blood samples, or other biological samples, overnight is not possible, but when viable living cells are required for diagnosis.